1 The registry change for REG_DWORD Value: 1 is not necessary when you are using the sample config:
http://www.cisco.com/warp/customer/707/2000.html
In this case, you are building LAN to LAN tunnel from a Cisco box to a Windows 2000 server.
If you are doing L2TP with IPSEC when you using remote access from a client to a Windows 2000 server, you do need the registry change for REG_DWORD Value: 1
2 I believe you are building up the tunnel from VPN 3000 to windows 2000 server ? In that case, you do not need worry about the user or group stuff, you should modify the LAN to LAN tunnel part of the IPSEC in VPN 3000 concentrator.
Other questions please clarify, then we will know what situation you are talking about. For example, remote-access for VPN client or LAN to LAN tunnel.
Best Regards,
Paul Qiu